This invention relates to beverage cans and can ends and more particularly to a beverage can end which is made of thin metal having a reinforcing peripheral structure and a gated opening comprising a large portion of, or all of, the center expansion panel.
The invention is especially suitable for drawn aluminum or steel cans for carbonated soft drinks and beer and more especially for drawn can bodies having necked-down tops. The necked-down body tops, reducing the size of the opening, permits the use of a smaller diameter can end formed of thinner metal. The economic advantages of this expedient are obvious and significant considering the amount of metal saved in the large number of cans manufactured each year. This savings suggests that the necked-down body top might be extended to reduce even further the size of the can opening and permit the use of a can end of even thinner metal having an even smaller diameter.
However, several factors prevent this reduction. First, the current lever-operated stay-on tabs, which are attached with a center panel rivet, would have to be formed with a lever and aperture too small to be practical for a gripping and lifting of the lever and for pouring or drinking directly from the can. Secondly, the conventional construction of an end will not permit the use of a significantly thinner metal because of internal pressures generated, as by carbonation. Such pressures could cause a deformation of the end known as buckling, which occurs when the chuck wall of the end pulls away from the double seam of the can. It is to be noted that spinner-neckers or multistage necking machinery can form a necked-down body of smaller diameter than presently used. Therefore, any use of a necked-down can for a smaller diameter end must be predicated on improved construction of the end itself.